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Assertion :- According to Lamarck, evolu...

Assertion :- According to Lamarck, evolution of life forms had occured but driven by use and disuse of organs.
Use and disuse of organ leads to change at genetic level.

A

If both Assertion & Reason are True & the Reason is a correct explanation of the Assertion.

B

If both Assertion & Reason are True but Reason is a not a correct explanation of the Assertion.

C

If Assertion is True but the Reason is False.

D

If both Assertion & Reason are false.

Text Solution

AI Generated Solution

The correct Answer is:
### Step-by-Step Solution: 1. **Understanding the Assertion**: - The assertion states that according to Lamarck, evolution of life forms occurred due to the use and disuse of organs. This is true. Lamarck proposed that organisms adapt to their environment through the use of certain organs, which become more developed, while unused organs may diminish or disappear over generations. 2. **Understanding the Reason**: - The reason claims that the use and disuse of organs lead to changes at the genetic level. This is false. Lamarck's theory does not involve genetic changes; rather, it focuses on the inheritance of acquired characteristics. Changes due to use and disuse occur in somatic cells and are not passed down genetically. 3. **Evaluating the Relationship**: - Since the assertion is true and the reason is false, we conclude that the reason does not correctly explain the assertion. 4. **Conclusion**: - The assertion is true, but the reason is false. Therefore, the correct answer is that the assertion is true, but the reason is not a correct explanation of the assertion. ### Final Answer: - Assertion: True - Reason: False
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Knowledge Check

  • The theory of use and disuse of organ was proposed by

    A
    Darwin
    B
    Lamarck
    C
    de Vries
    D
    Hooker

  • Given below are the three statement each with one or two blanks. Select the option which correctly fills up the balnks in any two statements. (A) For a long time it was also believed that life came out of decaying and rotting matter like straw, mud, etc. This was the theory of i (B) During post-industrilasiation period, the tree trunks became dark due to industrial smoke and soots. Under this condition the i did not survive due to predators, while ii survived. (C) Lamrack said that evolution of life forms had occurred but driven by i of organs.

    A
    i panspermia, i natural slection
    B
    i white-winged moth, ii dark-winged moth
    i use and disuse
    C
    i spontaneous generation
    i dark winged moth, ii white-winged moth
    D
    i eternity of life
    i use and disuse.

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